Piston or compression ring



F. MUELLER.

PISTON 0R COMPRESSION RING. APPLICATION FILED MAR-20.1919.

g'% 7' i 53, mum ,L x x: mum! PISTON 0R COMPRESSION RING.

Specification of Letters Patent.

Patented May 2, 1922.,

Application filed March 20, 1919. Serial I t'o. 283,847. 1

T 0 all whom it may concern:

Be it known that I, FREDERICK MUELLER, acitizen of the United States,residing at Irvington, in the county of Essex and State of New Jersey,have im'ented certain new and useful Improvements in Piston orCompression Rings; and I do hereby declare the following to be a full,clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame, reference being had to the accompanying drawings, and tocharacters of reference marked thereon, which form a part of thisspecification.

This invention relates, generally, to improvements in piston-rings; and,the present invention has reference, more particularly, to a novelconstruction of piston-ring adapted for use with engines of the variouskinds, and especially with internal explosive or combustion engines,such as are used with antomobiles.

My present invention, therefore, has for its principal object to providea novel and simply constructed piston-ring of the general characterhereinafter set forth, with a View of providing a piston-ring which canbe readily slipped over the end of the piston, without straining ordistorting the perfect annulus and outer fitting surface of the ring,the ring thus being adapted to maintain at all times a snug and evenlywearing connec-' tion between the piston and cylinder-wall.

Because of the shape of the interior surface of the annulus, providingpractically a re-inforced ring although made in one piece, the ring willnot be strained or will not break in placing itin position upon thepiston. will produce a perfect fit throughout its outer contactingsurfaceportions, thus economizing in the consumption of the explosivefuel, and at the same time will prevent the contacting surface of thering from becoming pitted or set with carbon.

Other objects of the present invention not at this time moreparticularly enumerated will be clearly understood from the followingdetailed description of the present invention.

With the above-stated objects in view, the present invention consists,primarily,-in the novel piston-ring of the general character andconstruction hereinafter more fully set,

forth.

The invention is clearly illustrated in the accompanying drawings, inwhich Figure l is a plan View of a completed piston-ring made accordingto and embodying the principles of the present invention; Figure 2 is anelevation of the same; and Figure 3 is a transverse vertical section ofsaid piston-ring.

Figure 4 is an enlarged detail vertical section of a portion of the saidring, said view illustrating moreclearly, one manner of providin theinterior surface of the ring with a mu tiplicity of alternating annularribs or raisedportions and annular grooves or depressed portions.

Figure 5 is a vertical sectional representation of a piece of tubing,illustratlng the various steps of the method for producing indicatecorresponding parts.

Referring now more particularly to Figures 1, 2, 3 and 4 of thedrawings, the reference-numeral 1 indicates the complete pistonring, thering in the present case consisting of a single annulus, having a jointformed by the two interlocking projecting end-portions or tongues '2 and3, as shown in Figure 2 of the drawings. In practice, I prefer to makethe interlocking projecting end-portions at their respective abuttingsurface -portions, when the ring is entirely closed, withconvexly-formed and concavely-formed cornerportions, as 4 and 5, adaptedto be brought into registration with each other, as shown in said Figure2, whereby the danger of the breaking away or cracking of the saidtongues due to crystallization or otherwise. as is so often the casewhere sharp corners are employed, is substantially overcome. As

shown more particularly in the drawings, the outer surface-portion 6 ofthe ring is a true cylinder, or when "iewed as shown in Figure 1, a truecircle. The opposite sides or planes '7 and 8 of the annulus arestraight, and the grooves ordepressions 10.

, according to the principles ofwithin the tubing, these parts arehighly mg for the cross-section, as will be clearly evident from aninspection of Figures 3 and at of the drawings.

ltllaving in the foregoing described the general construction ofvpiston-ring made the present invention, ll will nowbriefiy set forth thepreferred method of producing the same.

Referring now to Figure 5 of the draw ings, the reference-character 11,indicates a suitable length of tubing, preferably provided at one endwith a flange, as 12, for securing thesame in position at said end ofthe tubing to the head or chuck of a lathe.

The'normal thickness of the wall-portions of this tubing is indicated bythe longitudinally extending dotted lines 13 -13 in said Figure 5. Bymeans of the proper cutting tool, the inner'surface of the said tubingis cutaway so as to provide said surface with a multiplicity ofalternating annular ribs or raised portions It and annular grooves ordepressions 15 corresponding in configuration to the above mentionedannular ribs or raised portions 9 and annular After these ribs or raisedportions 14 and grooves on depressions 15 have been formed polished,andthen a rolling tool is inserted 1n the grooves," and'with theproperapplication of pressure, the channelled portions andiuniform'cylindrical surfaoe to. provide rings'of the desired size. .This turneddown l surface is next carefully polished, and the rings are thereuponremoved from the arbor. Each ring is next placed in a milling maLeia-re? chine andby-means of the proper milling tool the ring is milledacross its width to provide a split ring having previously mentionedinterlocking end-portions or tongues 2 and 3] Afterthe split ring hasbeen, in the above manner, finally completed, owing to the inner roundedmarginal edge-portions it can be easily slipped over the end of thepiston, and sprung into its packing position in the usual annular groovewith which the piston is provided' Clhe above-stated rolling operationhas produced thev ring with great resilient properties, so that the rinaccurately engages the inner wall of t e cylinder peripherally at allpoints. The perfect cylindrical contact insures a uniform wear of thering at all points, so that perfect com pression is the constant result,any leakage of the motive fluidfrom the one end of the piston in thatportion of the cylinder in which it is required to the opposite end ofthe piston being obviated. H

' ll claim I 1. A piston-ring comprising a single split annulus having atrue outer cylindrical and I smooth" contacting surface and straightsides, the inner annular surface-portion be- "ing provided with a seriesof annular ribs of convex cross-section and an intermediate annulardepression throughout of greater 7 density than said contacting surface.

2. A piston-ring comprising a singlesplit annulus having a true outercylindrical and smooth contacting surface and straight sides,.the innerannular surface-portion be ing provided with a multiplicity ofalternatingannular ribs of convex cross-section and annular depressionsof concave cross-sea tlon throughout of contacting surface.

greater density than said In testimony that l claim the invention setforth above l have hereunto set my hand this 17th dayof March, 1919. I

' FREDERICK MUELLER.

Witnessesf l nnon C. Fnann'rznn, Bantam Snr'rnunm.

